1. Field of the Invention
The present invention relates to a portable storage device, and more specifically, to a portable storage device having a sandwich package structure.
2. Description of the Prior Art
Most portable storage devices such as an MP3 player, a universal serial bus (USB) storage device, or a portable hard drive characterize with their small dimension for portability. A common USB storage device has its case made of plastic and assembled with snap fitting, screwing, or ultra sonic adhering. On the other hand, if the case of the USB storage device is made of metal or alloy, such as an aluminum extrusion case, the USB storage device is generally assembled by adhesive or screws, and the snap fitting way of assembly is not suitable for metal/alloy case since it is difficult to manufacture tiny size hooks with metal.
In the prior art, one type of package for portable storage devices includes a top cover and a bottom cover that jointly clip a print circuit board (PCB) as well as a flash memory and a USB connector so that the USB device is packaged inside the two-pieces case. Another type of package for portable storage devices includes a main housing where the PCB and the flash memory are fixed inside, the USB connector stretches out the main housing, and a cap covers the USB connector by directly wrapping the USB connector. However, both types of package for portable storage devices require one or more hooks or screws to assemble the case, which means the dimension of the products cannot be further reduced, or in other way of assembly, adhering the case together by adhesive or ultra sonic way, more manufacturing devices or materials are required.
Additionally, the prior art storage device usually has the cap directly wrapping and contacting the USB connector. Since the cap is a separable part each time the storage device is put to use, the repeated covering and removing of the cap from the USB connector may easily cause the USB connector to bend or wear in a short time.